A touchscreen is an input device layered on top of a visual display of a computing device. A user can make an input or control the computing device using single-touch or multi-touch gestures by contacting the touchscreen with a special stylus/pen or one or more fingers. Generally, the user can use the touchscreen to react to what is displayed and to control how it is displayed, for example, by panning around or zooming into what is being displayed.